The present disclosure relates to inkjet recording apparatuses.
An inkjet recording apparatus has, for example, a plurality of nozzles, pressurizing chambers, and piezoelectric elements. Ink droplets can be ejected from the plurality of nozzles. The pressurizing chambers are provided so as to communicate with the plurality of nozzles, respectively. Ink is charged into the pressurizing chambers. The piezoelectric elements are deformed by a driving voltage being applied, to eject, as ink droplets, the ink having been charged into the pressurizing chambers, from the nozzles.
Depending on an image formed on a recording paper, ink droplets may not be ejected from some of the plurality of nozzles for a long time period. The nozzles from which no ink droplets are ejected, are left in a state where a meniscus of ink is at a stop. In this case, for example, solvent contained in the ink near the meniscus evaporates, thereby increasing viscosity of the ink in the nozzles. As a result, ejection of ink droplets from the nozzles may be disturbed, or the nozzles may be clogged and thus ink droplets may not be ejected.
In recent years, an ink having a highly volatile solvent blended therein is used in order to enhance a quick-drying property for dots formed on a recording paper. Therefore, disturbance in ejection of ink droplets or non-ejecting of ink droplets as described above is more likely to occur.
On the other hand, a technique has been known in which a meniscus of an ink droplet is vibrated by minutely vibrating a piezoelectric element in order to reduce occurrence of non-ejecting of the ink droplets as described above and solve a problem that may arise after occurrence of the non-ejecting. In the technique, for example, ejection signal generation means that generates an ejection signal for ejecting ink, and minute-vibration signal generation means that periodically generates a minute-vibration signal for generating minute vibration to such a degree that ink does not eject, are provided. In the technique, waveform elements contained in the ejection signal and the minute-vibration signal are combined to generate a new driving pulse, the new driving pulse is inputted to a pressure generation element, and ink in a waiting state is minutely vibrated to prevent increase in viscosity of the ink.